NY NJ PA Weather Forecasts

Evening Thoughts

The model guidance this evening is giving us a prime example on how a strong ridge in the East doesn’t always translate to warm conditions for the forecast area.

The rainfall currently over the Ohio Valley will weaken as the upper trough supporting the rainfall splits and weakens.  Much of the PVA associated with this rainfall will lift north towards the St. Lawrence Valley, while another piece moves towards the Southeast and weakens significantly.

As a trough digs over the Northwest and northern Rockies, a ridge will build over the Southeast.  However, a strong upper low over eastern Quebec will produce an area of strong convergence and confluence over northern New England and the Canadian Maritimes.  As a result, strong high pressure will dominate the Northeast and impede the progression of the warm front over the forecast area and then push the warm front to the south completely.

Therefore, even though a strong upper ridge will be in place over the East, the Northeast and Mid Atlantic will remain average to slightly below average after a brief period of above average temperatures over the weekend.  

So to wrap this up, expect a warm front to move through on Thursday with a few showers and warmer temperatures through Sunday.  The warm front will be pushed back south as a back door cold front on Sunday evening, which will be followed with seasonably cool temperatures for the beginning of next week.  The position of the high pressure system may support a northeasterly component at the surface and more overcast conditions than currently expected due to the introduction of a marine environment.